Seagrass provides many ecosystem functions, such as high production, habitat provisioning or carbon sequestration. Such ecosystem functions often depend on seagrass biomass which shows distinct seasonal fluctuation reflecting variation in changes in environmental drivers, like temperature or irradiance. Although intertidal area is expected to be more susceptible to change in environmental factors, there is no integrated study on the effects of environmental factors on seasonal patterns of intertidal seagrass species.
In this study, we compiled data on seasonal patterns of two intertidal seagrass species, Zostera japonica and Z. noltii, across their distributional range and analyzed assembled data to investigate the effects of latitude and temperature on seagrass biomass and sexual reproduction. We hypothesized that 1) seagrass growth/reproductive patterns are affected by latitude and temperature and 2) latitude/temperature effects are consistent among seagrass species/distribution range.
From the analysis, we revealed that latitude and temperatures occasionally affect seagrass growth and reproduction, but trends are various among seagrass species and among analyzed parameters. Additionally, seagrass seasonality patterns are substantially different between tropical and temperate population, even within the same species. Our results suggest relative importance of local factors than large-scale factors like temperature on intertidal seagrass seasonal patterns, especially in temperate area.